Induction of suppressor cells in mice following Vaccinia virus infection.

Infection of mice with Vaccinia virus produced suppression of responsiveness of spleen cells to mitogens in vitro and suppression of delayed-type hypersensitivity in vivo. The latter suppression was transferred to normal mice by spleen cells of virus-infected mice. The data presented show that Vaccinia virus-induced immunosuppression involves the induction of suppressor cells which belong to both the adherent and non-adherent cell fractions.